Auto trans 68RFE in 2014 Dodge Ram 3500 adequate to tow 17,000 lb. Big Horn 5th Wh??

[cooperns1943]

Seriously shopping a new 2014 Dodge Ram 3500 with the 68RFE Automatic transmission and 3.42 rear axle gears. Is anyone out there with this new transmission pulling a big heavy 5th wheel 39 ft. and happy & comfortable with the performance? I have been used to pulling this 39 ft. 17,000 lb. fifth wheel with my 2005 Dodge Ram 2500 which has a 6 speed manual trans, 3.73 rear axle gears, and it has been awesome! I need convincing that this new transmission will be adequate compared to the new Aisin Trans. Really losing sleep over this issue while considering the new purchase. Anyone have experience here? Really appreciate this website just discovered for discussions. I am a longstanding subscriber of TDR and have found the information invaluable over the years.

5/30/14 Friday. Really appreciate the feedback. I am still processing and pondering. Really don't want to order but seems like just can't find what I really like on the lots between Grants Pass, Or and Washington. The Aisins are just not out there with the package I want without placing order. Most of my towing is between Rogue River-Grants Pass and the coast so only a few mountains passes to deal with. Perhaps we would do okay with the 1-ton 3500, 6 speed auto and 3.42 gears...I certainly would be mindful of dropping down to 5th or 4th manually when I sensed the need. Still thinkin' and will continue to watch for input. Thanks. Big time RV guy.

 

[Hoefler]

I have pulled my 40' fifth Wheel with my 2008 and 2010 equipped with the 68RFE, this transmission is very impressive! Has excellent cooling and is always in the right gear.

 

[RustyJC]

We've towed our previous 16K GVWR Mobile Suites 36RE3 and are now towing our 19K GVWR Mobile Suites 38RSSA with the truck in my signature. The only problem we've had with the 68RFE was one instance when we weren't even towing - it kicked a check engine light and went into limp (no auto shifting, and wouldn't manually shift above 4th gear) mode. The dealer found a failed output speed sensor and a bad solenoid. Both were replaced under the powertrain warranty. Other than that, the 68RFE has been trouble-free. Trans temp on the EVIC runs 165 degF with the previous 5th wheel and 172 degF with the current one on the Interstate at 65 MPH.

Rusty

 

[Jim W]

Will the 68RFE is not really that new since it was introduced in Jan 2007 on the 2007.5 6.7L trucks.

I bought my truck new in Nov of 07, a 2008, 2500 Mega Cab, SB, 6.7L, 68RFE,4X4 with 3:73 gears. I have driven this truck as a daily driver and towed two different 5er's with it. I am pulling a 11K 5er that is 35 FT long. I have serviced the transmission twice now just filters and transmission fluids, no other issues with the transmission.

I am running about 60HP over stock at the rear axle and have been this way since Aug 09. I am extremely impressed with the transmission and feel that the transmission is just as reliable as any other big three automatic truck transmission that are for sale on the new trucks today.

I know a little bit of the design history on the 68RFE and was informed that the case was designed by Chrysler and the gear set and workings was designed by MB when they owned Chrysler. I had a contract engineer who worked for me at Cat who worked on the case line at Chrysler when he was going to school in Indiana. Who stated this when I was trying to decided on a new diesel tow vehicle when buying. So this is not like their other automatics that Chrysler offered in the pass. In fact there are no transmission bands that need adjusting as the previous ones required. As long as the transmission is not abused it will provide reliable service.


Jim W

 

[p-Bar]

Why wouldn't you get one with the Aisin Trans ? price point? My transmission guy thinks a built 48RE is better than the 68RFE . As stated above not enough miles and time on these RFE's . As much as you are paying for your truck go Aisin

 

[Ram4Sam]

Given the size of your trailer and the 3.42 gears, I would spend the extra $2000 for the aisin trans.....

Sam

 

[Dieselnerd]

My vote goes to the Aisin also. Unless money is a problem, why settle for adequate when you can have unbreakable?

 

[Gonzo 1066]

My 2013 has 10,000 towing miles on the 68rfe and so far I am quite impressed. Seems to always be in the correct gear, stays cool and coming down mountain grades it integrates with the exhaust brake very well.

 

[Larry Willard]

I had an '08 with the 68RFE, it was my first auto and I was impressed with it. I now have a '13 with the Aisin and there is no comparison, it runs cooler, always has the right gear, and the exhaust brake works way better. I would spend the extra money and upgrade to the best transmission to go along with the best engine.
Larry

 

[Powder Extreme]

I own both in a '13 and '14. Hands down the Aisin is the way to go. Sure, the 68rfe might be adequate, but if adequate is "good enough" because of price, you might as well save another chunk of change and go with the gasser. The new Hemi will yank the trailer around just fine. Honestly, it will probably do a better job than the Cummins did 20 yrs ago, and back then we were dragging trailers all over the place with only 175hp, 420tq and just as happy as a pig in you know what.

 

[RustyJC]

While I agree that, if I were ordering a new truck, it would be an Aisin, the OP's question was "Is the 68RFE adequate to tow a 17K 5th wheel?" I believe that, based on my experience and that of the other posters, the answer to the OP's question is yes.

Rusty

 

[Cummins12V98]

I have 50K on my 11 HO Dually with 68RFE 3:42's with zero problems combined weight of 28K+. I am very impressed!

Saying that when I get a 15 with rear air ride it will have the Aisin and 4:10's

 

[RVTRKN]

No lower than 3:73 gears and you will be fine. At that weight though, I would go with 4:10.

 

[Wertles]

No lower than 3:73 gears and you will be fine. At that weight though, I would go with 4:10.

My trailer is 18K. I have the 4.10's. Wish I had the 3:73's instead. The 13/14 trucks have so much power that unless you are well over 20K, there is no need. I'd rather take the little better fuel economy unloaded and the occasional shift to fifth gear while towing.

 

[Cummins12V98]

Does anyone know for a FACT that the 3 different gear ratios will produce different mileage unloaded?

 

[RVTRKN]

At three different RPM's for the same speed, its a no brainer, 3:42 is like climbing a perpetual grade, compared to 4:10's.

 

[S.Morris]

If I was going with the 68rfe I would want to have 4.10 ratio diffs pulling that weight over the long haul/.
#1 choice would be aisin and 3.73.

 

[PC12Driver]

The 68RFE will do just fine. My transmission temp barely moves with the 40' 5ver in tow, even with my foot in it on long grades.

Keep in mind that the final drive ratio of 6th with 4.10s is about the same as 5th with 3.42s. Just lock it down to 5th with the trailer on and have the tall OD available when bobtailing. Slower turning driveline means less parasitic loss (drag) as well.

 

[RustyJC]

Keep in mind that the final drive ratio of 6th with 4.10s is about the same as 5th with 3.42s. Just lock it down to 5th with the trailer on and have the tall OD available when bobtailing. Slower turning driveline means less parasitic loss (drag) as well.

Interesting philosophy in support of 3.42 gearing, but personally I'd rather have 6 than 5 gears available when towing the 5th wheel in my signature. Also, a slower turning driveline means that all the components upstream of the ring gear are having to transmit more torque for a given rear wheel torque and speed. Since BHP = (Torque x RPM) / 5252, then a decrease in driveline speed means a proportional increase in driveline torque for a given rear wheel horsepower and speed. There's a reason that rated GCWR increases as differential gearing goes lower (higher numerically).

Rusty

 

[Cummins12V98]

When i came on here and I mentioned I had the 3:42 gears I knew they were not the best for 28K combined and several said the sky was falling!

I only have one thing that is not great with the 3:42's it's taking off on a steep grade.

So to cure that one problem I will have the 4:10's in the 15 I get this fall.

One thing I find interesting my Dad has 3:73" in a 12 2wd same truck as mine. He said he was to the floor heading north on I-5 just before the summit on Ashland pass coming into Oregon. He said he was in 3rd and 50mph. I have pulled the same spot several times at 55mph in 3rd also. I am 28K+ and he is 24-25 Max.